Ischemia generally refers to a restriction in blood supply. Myocardial ischemia is a type of ischemia characterized by inadequate blood supply to the heart muscle. Generally speaking, two types of myocardial ischemia exist. The first is demand ischemia, which is associated with increased oxygen demand due to increased metabolism in the heart muscle. The second is supply ischemia, which is associated with decreased oxygen supply due to restricted blood flow in the coronary artery. Demand ischemia can happen during times of physical exertion or emotion stress, or even while at rest in severe cases.
Ischemic heart disease may present any number of problems. One such problem is angina pectoris, where myocardial ischemia manifests as chest pain experienced by a person during exertion, in cold weather, during emotional situations, or spontaneously due to coronary vasospasm, among other situations. Refraining from exertion, avoiding cold weather, or calming can sometimes address an episode of chest pain.
Further manifestations of myocardial ischemia include acute chest pain, reduced physical capabilities, unstable angina, and myocardial infarction (heart attack). Myocardial ischemia in such manifestations is often not relieved by removing a stressor or resting the patient. Acute heart damage can also result if the ischemic episode is severe or prolonged enough. Progression of myocardial ischemia can lead to heart failure, which is associated with difficulty in breathing, fatigue, swelling of the extremities due to inadequate circulation, and death.
Several treatment options for myocardial ischemia exist. For example, lifestyle changes, such as cessation of smoking, increasing physical activity, and weight optimization can help limit the progression of myocardial ischemia associated with heart disease. Drugs can also be used to relieve symptoms, such as angina, as well as slow the progression of the disease. Addressing other diseases, such as diabetes, can also improve a patient's heart condition. For example, daily aspirin or beta blocking drugs may slow progression, while nitroglycerin can be used to address specific episodes.